perf(cli): TTFT round 2 — live reasoning by default, partial-line streaming, prompt-build cache, stale budget-warning docs (#59389)

Follow-up to #59332 targeting the remaining PERCEIVED first-token latency
(the wire streaming was already per-token; these fix what the user sees):

1. display.show_reasoning default ON. On thinking models the reasoning
   phase streams for tens of seconds; with the display off users stare
   at a spinner the whole time and read it as a stall. Flipped in
   DEFAULT_CONFIG, load_cli_config defaults, tui_gateway raw-YAML
   fallbacks, and the hermes setup status line (all four read sites kept
   in sync). Gateway per-platform defaults intentionally stay off —
   messaging chats shouldn't fill with thinking text. /reasoning hide
   still turns it off and persists.

2. Response box force-flushes long partial lines. _emit_stream_text only
   painted on newline, so a response opening with a long paragraph
   stayed invisible until the first \n — seconds of blank box. Now
   partial lines wrap at terminal width and paint as tokens arrive
   (mirrors the reasoning box's 80-char force-flush that existed since
   day one). Table blocks remain batch-aligned; no content loss at wrap
   boundaries (regression tests added).

3. hermes_time timezone resolution uses read_raw_config (mtime-cached +
   libyaml C loader) instead of a raw yaml.safe_load of config.yaml
   (~110-140ms measured) inside the FIRST system prompt build. First
   build drops 320ms -> ~155ms on a 200-skill install.

4. Stale docs: configuration.md (en+zh) still documented the 70%/90%
   [BUDGET WARNING] tool-result injections. Those were removed in April
   2026 (c8aff7463) precisely because they hurt task completion; current
   behavior is exhaustion-message + one grace call, no mid-loop
   injection, no cache impact. Docs now describe reality.

Verified: token-count compression decisions already use API-reported
last_prompt_tokens (rough estimators are preflight-only and cost ~1.7ms
even on 1.7MB histories — not worth touching).

tests/cli/test_reasoning_command.py

@@ -550,7 +550,10 @@ class TestConfigDefault(unittest.TestCase):
         from hermes_cli.config import DEFAULT_CONFIG
         display = DEFAULT_CONFIG.get("display", {})
         self.assertIn("show_reasoning", display)
-        self.assertFalse(display["show_reasoning"])
+        # Default ON (July 2026 TTFT-perception change): thinking models
+        # stream reasoning for tens of seconds; hiding it left users staring
+        # at a spinner. The key must exist and be a bool.
+        self.assertTrue(display["show_reasoning"])
 
 
 class TestCommandRegistered(unittest.TestCase):